Improvement in hydraulic jacks



D.L. WEAVER & G. NOBLE.

HYDRAULIC JACK.

No. 192,472. Patented June 26,1877.

. jack for testing bridge-bolts, and for adjust- UNITED STATES FFIOEOPATENT IMPROVEMENT IN HYDRAULIC JACK S.

Specification forming part of Letters Patent No. 192,472, dated June 26,1877; application filed April 30, 1877. I

Be it known that we, DANIEL L. WEAVER and GEORGE NOBLE, of Hunuewell,Greenup county, Kentucky, have invented a new and useful Improvement inHydraulic Jacks, of which the following is a specification:

Figure l is a side elevation, and Fig. 2 is a front elevation.

The object of our invention is to provide a ing them to the properdegree of tension, so that the strain upon the several bolts in a bridgemay be evenlydistributed.

In the drawing, A is the cylinder of the jack, which is provided withthe usual pump for forcing water into the barrel containing the piston,which is worked by the lever a. B is a yoke for supporting the piston O,and D is an annular base-piece, to which the said yoke is attached. E Eare bars attached to the cylinder A, and also to a head, F, placedwithin the yoke 13. The head F'is mortise-d vertically to receive theshank of the socketnnt G, and is inortised transversely to receive thekey H, which also passes through the shank of nut G. A pressure-gage, I,is connected with the cylinder A, having a dial, the graduations ofwhich represent diflerent sizes of bolts, the graduations being arrangedwith reference to the strain to be put upon the bolt,

so that when the index is opposite the figures on the dial representingthe size of the bolt under strain the limit of tension is reached,

and the pressure is not further increased.

The manner of using the improved jack is as follows: The annularbase-piece D is placed on some portion of the bridge over the end of thebolt 1) to be tested or adjusted; the sock et-nut G is screwed on theend of the bolt, and the cylinder A is let down until the shank of thenut G is received by the mortise of the head F, when the key H isinserted and the lever a is worked until the index of the pressure-gagestands at the number representing .the bolt under strain; the pump isthen stopped, and the nut upon the bolt is turned down to its seat.

Having thus described our invention, we claim as new and desire tosecure by Letters Patent-- 1. The yoke 13, piston 0, cylinder A, bars E,and inortised head F in combination, substantially as herein shown anddescribed.

2. The combination of the socket-nut G and head F, substantially as andfor the purpose shown and described. I

DANIEL L. WEAVER. GEORGE NOBLE. Witnesses:

SEBASTIAN EIFONT, CHARLES WHITTINGTON.

